STOCKHOLM, Sweden -- A one-of-a-kind vending machine on the campus of the Royal Institute of Technology this month got students into the holiday spirit by inviting them to sing their favorite Christmas carols for a free Coke.

The closed-front beverage vender, adorned with snowflakes, a Christmas tree and the words "Sjung for mig" (sing for me), was equipped with a karaoke machine and touchscreen panel. College coeds selected their favorite Christmas carol, picked up a microphone mounted in place of a payment system and started singing.

When they finished their song, they received a bottle of Coca-Cola, which was dispensed through the delivery door by a person concealed in the machine enclosure.

"We took turns and I sat there for a good two hours. It was lots of fun hearing all the singing and handing out bottles of Coke," JMW's Samuel Garlöv told Vending Times. "Because the machine was placed at the Royal Institute of Technology, it didn't take the students long before the figured out how the machine worked. But they liked the old-school manpowered function of the machine and started discussing how you would build a 2.0 version."